Iminopyrazolone coupler for color photography



-(S3 Rttttiuiut 3 m 5 IMINOPYRAZOLONE COUPLER FOR COLOR PHOTOGRAPHY Henry D. Porter and Arnold Weissberger, Rochester, N. Y., assignors to Eastman Kodak Company, Rochester, N. a corporation of New Jersey No Drawing.

Application November 14, 1941,

Serial No. 419,172

8 Claims.

This invention relates to photographic color forming compounds and particularly to iminopyrazolone coupler compounds for color forming processes of color photography. The formation of colored photographic images ,5 by coupling the development product of aromatic O amino developing agents with color forming or 1 pheuy1 amydmy flgpmsylimmopmmlone coupling compounds is well known. In these N=C OH processes the subtractive process of color formation is ordinarily used and the image dyes are 10 (3) intended to be of the complementary primary o-cm colors cyan or blue-green, magenta, and yellow. The couplers which produce the cyan dyes are N- so,Nm usually phenols or naphthols, those producing th t dy are di il yr l or 154 l-phenyl-3-hydroxy-5-sulfamylphenyliminopyrazolona cyano acetyl compounds, and those producing the yellow dyes are ordinarily compounds containing (4) O a methylene group having two carbonyl groups attached to it. The dyes produced by coupling are azomethines, indamines or indophenols de- O Q pending upon the composition of the coupler and Of the developer. l-phenyle-hydroxy-ap(p-tert. amy1phenoxy)-phenylimiuo- In our copending application Serial No. 412,244, filed September 25, 1941, we have shown that the The novel couplers of our invention are proacyliminopyrazolone couplers have valuable propduced by treatment of an unsubstituted imino erties for purposes of color photography. We have found that the non-acylated iminopyrazclone couplers also possess valuable properties pyrazolone with the suitable aromatic amine according to the following reaction:

for the production of magenta dyes in color RN +NH3 forming methods of color photography. Our H H novel couplers have the following general for- T mula: NH

N=COli Our couplers are designed for use in processes in which the coupler is incorporated in the de- CH veloping solution such as those described in. Mannes and Godowsky U. s. Patent 2,113,329, granted April 5, 1938, or Marines, Godowskyand l-phenyl-3-hydroxy-fi-phenyliminopyrazolone o: useli- Wilder U. S. Patent 2,252,718, granted August 19, 1941. Certain of the couplers of our invention may be incorporated in sensitive emulsion layers for use in processes such as those described in Fischer U. S. Patent 1,055,155, granted March 4, 1913, Mannes and Godowsky U. S. applications Serial Nos. 314,688 and 314,689, filed January 19, 1940, and Jelley and Vittum U. S. application Serial No. 371,612, filed December 26, 1940.

The following examples illustrate developing solutions containing the couplers used according to our invention:

Example 1 A. 2-amino-5-diethylaminotoluene hydrochloride grams 2 Sodium sulfite (anhydrous) do 2 Sodium carbonate (anhydrous) do 20 Potassium bromide do 1 Water to liter 1 B. 1- phenyl 3 hydroxy 5 phenyliminopyrazolone grams 2 Sodium hydroxide solution) cc 10 B is added to A Example 2 A. Dimethyl-p-phenylenediamine sulfate grams 3 Sodium sulfite (anhydrous) do 5 Sodium carbonate (anhydrous) do 20 Potassium bromide do 2 Water to liter 1 B. l-phenyl-B-hydroxy 5 sulfamylphenyliminopyraziolone "grams" 3 Isopropyl alcohol cc 100 B is added to A The foregoing examples refer to the addition of the coupler compound to the developing solution itself. The coupler may also be added to the emulsion layer provided that suitable means are used to prevent its diffusion in the case of mutilayer coatings. Special dispersing agents may be used for incorporating the coupler compound in the emulsion and in certain cases the coupler may be absorbed or adsorbed to the sensitive salt or may be combined with the sensitive salt as a chemical combination. Certain of the coupler compounds described in the present application such as No. 4 are in themselves nondifiusing and may be incorporated in the photographic layer without the use of additional agents to prevent diffusion. This coupler may also be incorporated in an emulsion layer according to the methods of Mannes and Godowsky U. S. application Serial No. 314,689 and Jelley and Vittum U. S. application Serial No. 371,612, referred to above.

We are aware that 1-phenyl-3-hydroxy-5- lminopyrazolone has been described in British Patent 478,990 for use as a coupler. The iminopyrazolones of the present invention, however, are superior in light absorption characteristics to the unsubstituted iminopyrazolone.

In the development of exposed photographic silver halide emulsion layers, using the couplers of our invention, any color forming developer containing a primary amino group may be used. These include developers having two primary amino groups as well as those having one of the amino groups substituted or having substituents in the ring such as alkyl phenylenediamines and alkyl toluylene diamines. These compounds are usually used in the salt form such as the hydrochloride or the sulfate which are more stable than the amines themselves. The suitable compounds are diethyl-p-phenylenediamine hydrochloride, monomethyl-p-phenylenediamine hydrochloride, dimethyl-p-phenylenediamine hydrochloride and 2-amino-5-diethylaminotoluene hydrochloride. The p-amino phenols and their substitution products may also be used where the amino group is unsubstituted. All of these developers have an unsubstituted amino group which enables the oxidation products of the developer to couple with the color forming compounds to form a dye image.

Our development process may be employed for the production of colored photographic images in layers of gelatin or other carriers, such as collodion. organic esters of cellulose, or synthetic resins. The carrier may be supported by a transparent medium such as glass. a cellulose ester or a non-transparent reflecting medium such as paper or an opaque cellulose ester. The emulsion may be coated as a single layer on the support or as superposed layers on one or both sides of the support. The superposed layers may be differentially sensitized and the dyes formed therein by coupling may be bleached by an oxidizing agent such as chromic acid to colorless soluble compounds. The destruction of the dye in this way does not destroy the silver image and a silver image may be developed, bleached and develoyed to color images in superposed layers as described, for example, in Mannes and Godowsky U. S. Patent No. 2,113,329.

The examples and compounds set forth in the present specification are illustrative only and it is to be understood that our invention is to be taken as limited only by the scope of the appended claims.

We claim:

1. A color forming photographic developer comprising a primary'aromatic amino developing agent and a coupler compound having the formula:

4. A color forming photographic developer comprising a primary aromatic amino developing agent and a coupler compound having the formula:

5. The method of producing a magenta colored photographic image in a gelatino silver halide emulsion layer which comprises exposing the layer and developing it with a primary aromatic amino developing agent in the presence of a coupler compound having the formula:

N=COH RN\ ([iCH1 N-R in which R and R are aryl groups.

6. The method of producing a magenta colored photographic image in a gelatino silver halide emulsion layer which comprises exposing the layer and developing it with a primary aromatic amino developing agent in the presence of a coupler compound having the formula:

N=C-OH RN\ (FT-CH2 N-R in which R and R are aryl groups of the benzene series.

'7. A photographic emulsion for forming colored Search Room images comprising a colloidal carrier containing a sensitive silver halide and a coupler compound having the formula:

in which R. and R are aryl radicals.

8. A photographic emulsion for forming colored images comprising a gelatino-silver halide emulsion containing a coupler compound having the following general formula:

HENRY D. PORTER. ARNOLD WEISSBERGER. 

